Apparatus for cutting venetian blind tapes



Oct. 4, 1949.

APPARATUS FOR Filed May 28, 1948 G. S. MACK CUTTING VENETIAN BLIND TAPES 6 Sheets-Sheet l GEORGE 5. MACK.

Ema/whom! v Oct. 4, 1949. G. s. MACK APPARATUS FOR CUTTING VENETIAN BLIND- TAPES S-Sheets-Sheet 2 Filed May 28, 1948 Oct. 4, 1949. I G. s, MACK 2,483,587

APPARATUS FOR CUTTI NG VENETIAN BLIND TAPES Filed May 28, 1948 6 Sheets-Sheet 3 J r-/47 I33 k I if: GEORGE Mgg Oct. 4, 1949. G. s. MACK CUTTING VENETIAN ELI-ND TAPES APPARATUS FOR 6 Sheets-Sheet 4 .Filed May 28, 1948 GEORGE S. MACK,

Oct. 4, 1949. .G. s. MACK 2,483,587 ,u

APPARATUS FOR CUTTING VENETIAN BLIND TAPES Filed May 28, 1948 v 6 Sheets-Sheet 5 GEORGE S. MfiCK.

' Swan/who'vmu Y Oct. 4, 1949'.

G. s. MACK APPARATUS FOR CUTTING VENETIAN BLIND TAPES 6 Sheets-Sheet 6 Filed May 2 1948 Gtmes S. MACK Patented Oct. 4, 1949 UNITED APPARATUS FOR CUTTING VENETIAN BLIND TAPES George S. Mack, Anderson, S. 0.

Application May 28, 1948, Serial No. 29,825

This invention relates to severing means adapted to be applied to a loom on which the weaving of multi-woven tapes or webs of the ladder type, such as are used for supporting the slats of Venetian blinds, is effected. I

This invention relates more especially to apparatus to be applied to a loom for severing crossover warp threads and the like between two superposed tapes and interconnecting straps, all of which are woven at the same time, so that the superposed tapes may be drawn apart from each other and will have disposed therebetween the interconnecting warp threads or straps, on which the slats of the Venetian blind are adapted to rest.

It is a well known fact, to those familiar with the art, that Venetian blind tapes consist of two body tapes which are woven simultaneously with connecting tapes or straps. The connecting straps are arranged in two parallel rows adjacent the opposite edges of the body tapes and, until these cross-over warp threads are severed, in the manner to be later described, the body tapes cannot be separated to form the ladder structure.

Heretofore, the severing of the cross-over threads has been done by various means, such as manually, or by machines removed from the loom,

or in some instances they have been severed on the.

loom. However, the means heretofore used on looms for severing the cross-over threads has not been satisfactory in that it has been expensive to manufacture and has depended upon the function of various other parts of the loom which are disposed some distance away from the point at which the severing operation is to be performed on the loom.

It is an object of this invention to provide means driven by the rock shaft of a loom for alternately severing the cross-over threads, disposed between the two body tapes as they are woven On a loom, to thus form the ladder tapes heretofore described.

It is another object of this invention to provide means in combination with a loom for intermittently moving a pair of cutters, one at a time, between a pair of superposed body tapes, so that each of the cutter blades will alternately perform the operation of severing the cross-over threads disposed between the body tapes and to also provide means for oscillating the cutter blades in a vertical plane as as to assist in severing the crossover threads, thereby assuring a smooth even edge to the threads that have been severed.

It is another object of this invention to provide a means for severing the cross-over threads at precisely the point intended in the tape so that in 12 Claims. (Cl. 139291) the event the conventional pick gearing has become out of proper timed relation, one of the blades would sever one of the connecting straps between the two main body tapes instead of the cross-over threads, which would serve as a warning to the operator of the loom that the correct number of picks were not being woven into the inter-woven portions on the connecting straps and the main body tapes.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in which Figure 1 is a front elevation of the lower part of a loom, that is, from the breast beam down to the floor, showing the apparatus applied thereto;

Figure 2 is an elevation, partly in section, and being taken along the line 22 in Figure 1 and showing various other parts of the loom schematically;

Figure 3 is an enlarged rear elevation of the driving mechanism associated with this invention and is taken along the line 3-3 in Figure 2 and being a reverse elevation of the lower central portion of Figure 1;

Figure 4 is an enlarged end elevation of one of the bearing blocks associated with this device and is taken along the line 44 in Figure 1;

Figure 5 is an enlarged vertical sectional view taken along the line 55 in Figure 1;

Figure 6 is an enlarged elevation of the driving mechanism associated with the thread cutting mechanism and is taken along the line 6-6 in Figure 1;

Figure 7 is an enlarged elevation of the cutting means associated with one of the interconnected tapes and is an elevation of the opposite side of the central portion of Figure 1;

Figures is an elevation looking from the righthand side of Figure 1 to the left, showing a portion of the loom frame and showing the lay in its rearmost position;

Figure 9 is an enlarged elevation with parts in section and is taken along the line 99 in Figure '7;

Figure 10 is an enlarged vertical sectional view showing that means which is nearest the observer in Figure 6 for connecting the cable to the lever arm associated therewith and is taken along the line Ill-l0 in Figure 6;

Figure 11 is a top plan view of the central structure shown in Figure 1 and is taken along the line llll in Figure 1;

Figure 12 is an isometric view of a portion of the ladder tape as it is after it is removed from an 3 ordinary loom before the cross-over warp threads have been severed;

Figure 13 is an isometric view of a portion of the finished ladder tape after the cross-over threads have been cut and with the body tapes disposed in spaced relation to each other for receiving the slat of a Venetian blind.

Referring more specifically to the drawings, the numerals I and H indicate therright and left hand side'frame members of a loom frame respectively which have disposed therebetween intermediate frame members or struts I2, only one of which is shown, and the side framermembers I 0 and H and the members I2 are interconnected by a breast beam 14 disposed on the upper front ends of the same. The rear ends of the sidefranie members l0 and II, as well as the.,.interme diate frame members [2, are interconnectedby an' I beam l5 (Figure 2).

The side frame members and H havedown wardly projecting bearing portions and-2 I re spectively in whichthe opposite ends of :-a con ventional rocker shaft 22 are oscillatably mounted. The rocker shaft-22 has fixedly secured thereon conventional upwardly projectingswords 24 and 25 -whichehavesecured i-to their upper; ends, by boltsflil; a lay 30 tQpWhiCh the lower *ends of aplurality-gof reedimembers; 3! are secured, their upper ends being secured adjacent the lower edge 0:713, conventional reed cap :32 -which, on "this particulartype of loom, are:,connected to the lay by interconnecting strap iron members 34 disposed at each end of-thelayfl iguret);

- ;e-;The vertica-l-strap nonmembers- 34 have studs 35 penetrating the same "which'have rotatably mounted thereongrooved pulleys 36 which? have a.beltSLmountedonthesamel-one end of which is connected=to -a conventional driving-meanspnot shown, and the :other end of which is. connected to a series of conventional gear racks, not shown; disposed in longitudinally extending grooves 38 and- 39 in the reed cap '132 -andthe lay respectively; which, are adapted -to.;transmitreciproca= tory motion, -;by conventional' means, not shown,

to a pluralityof upper shuttlesi ahdlower shuttles :5 Ldisposed vbetween they lay; v30 and the reed cap 32.

The swords 24 r :25 have pivoted:(thereto;- adiacenmthelay :30; pitmanrods: 54 =,and-' 55, re-

spectively (Figures2 and 8-). 'Thesevpitmanrods means, not shown, and, there is disposed there below, a'conventional zcam shaft :WhiCh-iS.10-i tatably mounted in the iside frame members :10 and-H and is also rotatably mounted in bearing blocked! fixedly mounted onatheintermediate frame members [2 (Figure 2). ;Thelshaft 60 1s driven by conventional means, not shown.

, Theloom hasa plurality of sheets of warp arns which extend frompsuitable creels or a warp beam, not shown, and pass through suitable harnesses 68 (Figure 2). The'warpv threads then extend from the harnesses 68 through the reeds3l to form a plurality of unfinished ladder tapes broadly designated at 15.: qp.:;

, These tapes 15 are made-.upof-twosuperposed parallel body tapes, or webs 161 and1l, .(Eigures 'L, v12 and- 13 with two spaced rows of connecting tapes or cross straps l8 and 19 interwovenithere V betweerng The structure; of the compositetapeis fully shown and disclosed in Patents v,numered 4 2,226,093 of December 14, 1940, and 2,080,831 of May 18, 1937.

The ladder web or tape 15 is woven with the connecting tapes or cross straps being disposed approximately & of an inch inwardly from each edge of the body tapes '6 and H. The warp threads forming the connecting tapes l8 and I9 are interwoven with the tape H as at 82 and 83 and are then interwoven with the tape '16 as at 89-and BI. This causes cross-over warp threads 85 and 86 to be disposed between the interwoven spots 82 and and BI and 83 respectively. When so woven, thecross-over warp threads and 86 respectively must be severed before the two body tapes I6 and H can be separated as shown in Figure 13 toreceive the slats of a Venetian blind. It may =be,..observed in Figures 12 and 13 that the portions" 82 of the straps 18 are equally spaced apartfrom each other and the intervowen portions 83 of the cross-straps 19 are so arranged longitudinally of the tape: 15 as,to--:ber; disposed midwayof the interwoven portions; 821a-t theppez posite edge of the tape 15, the portions83. also being spaced equal distances, apart ,;from =;eachother throughout the entire lengthfof the; tape 15 and beingin staggered relation to the interwoven portions 82 disposed in the opposite side :of the tape.

Now, the ladder'tapes 15; extend from the beat the front surface ofthesame and then arounda plurality f ke-up orsand rolls 90 Whi'ch"-'are fixedly mounted ona transverse-shaftl-ll which'is rotatably mounted; at each 'end::;thereof;' in the side frame membersld'and 1|. Theshaft 9| has a conventional'pick gear wheel 92 (Figured-) fixedly mounted thereon, adjacent 'the verti'c'al side frame member ID, which engagesa pinion 93 fixedlytmountedon a shaf-t which is rotatably .mounted in :the vertical side frame member I 0 and has fixedly mounted on the other end thereof a ratchet wheel 95. .xDispoSed between the wheel 95 and the vertical side frame'member 10 (Figure 1) is a bell crank lever 96 .0 having an upwardly extending: arm-; 91 integral therewith (Figures 1 and 8). t wheel 95 is engaged byratchet pawls-l I0 and-l H one of which is pivotally mounted on the arm 91', and the other of which is pivotally mounted on the side frame member l0. The bellcrank lever 96 has pivotallyconnected adjacentthe lowerend thereofa link member H2 whichextends rear wardly and is-secured to a conventional upwardly extending arm H4, as at H3. The arm IMhas,

integral therewith, a horizontally disposed portion-J15 .(Figure 1), which is secured, by a bolt H6, to the front surface-of the sword-244 The tion-to the gear 92 by means-of the pinion '93,

and theshaft SI on which the take-up rollers 90 are fixedly secured, to thus take up the ladder tapes (5 in- -a ste'p -by- -step-relation each time the lay moves to a for-ward or beat-up position.

The -.tapes after passing around -a--'portion"of the-periphery of-the take-up rollers 90 are di--- The ratchet assess? eqt dsoveridlersroll rs.1120 (Fi r s 1- and 2).. which are rotatably mounted on conventional U hapesiemem s 2! which are. pivot ly mounted,; as ;at; -I22, to-downwardly-projecting screw y f el i whichare secured in the lower-surface of the horizontallydisposed breast beam I4. The. tapes 15 then-pass rearwardly t o;a suitable means for winding up the same, not, shown; ."All ofthe parts which have-heretoforebeen described are conventional anditds with these parts .that this invention-is adapted to ;be associated.

Now,;;as thetapes; 15' pass downwardly from; the breast beam- I4, the cross-over warp threads; 95;and;86 are severed before the, tapes15 engage the tape take-up rolls 90: --It may be'observed in Figures '1 and Qthat-only: one of .the sets of. cross-over threads ;85 .0r 8 6.are severed at one time on; each of the; laclde r tapes 15. Figure 7 shows aknife I25 in;a;.psiti0n ready to sever the, cross-over threads 85, theybeing disposed adjacent and above ,p he interwoven portion 83, and, ,-in this instance, the cutter blade I25 is shown to be 'partially disposed between the body tapes 16 and "and extends inwardly from one edge: of the same to the center of the same and simultaneously there is projecting slightly inwardlytbetween thebodytapes 16 and 11, at the opposite edge thereof, a second blade I26 and it w-ill. be noted thatthis blade I26 is not in the path of the interconnecting straps 18 while the blade I25 is in the pathof the connecting tapes 1 9. -I-Iowever, as soon as the blade I25 has severed the threads 86', the blades I25 and i 26 then'move from left-to right in Figure 7 so that the blade I26 is in alignment with the connecting tapes 18-t0 thus sever the cross-over warp threads85 and thus the knife I25 allows the connecting tapes19-to pass Without being severed. These blades I25 and I26 are caused to move back and forth simultaneously in step by 'step .relationso that the cross-over threads 85' and 86 of each of the tapes 15 will thus be severed by the blades I25'and I26 as the body tapes 16 and 11 pass thereby. The means of transmitting the reciprocatory motion to the blades I25 and I26 is to be presently described.

There is one of each'of these blades I25 and I26 disposed adjacent the sides of each of the tapes 15 in the identical manner to that shown in Figure '1, and these blades I25 and I26 are each'secured to a block I21, by any suitablemeans such as a bolt I28. This block I21 is fixedly secured'o'n astub shaft I39, by any suitable means'such as a set screw I3I. The stub shaft I30 is integral with a cuii member or block I32 which is adjustably mounted on a rectangular shaft I33 and is secured to the same by a set screw I34.

The shaft I33 extends from the vertical side; frame member I0 to the vertical side frame member II and is mounted at each end thereof in bearing blocks I40 and MI, respectively, and this shaft I33 has vertical reciprocatory movement inthe bearing blocks I40 and MI inasmuch as the bearing blocks I49 and MI have slots I42 in the-same which permit the vertical'motion, said motion being transmitted to the shaft I33 in a manner to be later described.

-Th shaft I33 also has lateral or longitudinal sliding movement in the blocks I40 and MI and this'longitudinal motion is transmitted to the same by means of cables I43 and I44. The cables I43 and I44-are connected at one of their end's to -screw-eyes I46 (Figures 1 and each' 0f= which -is threadably imbedded in a block -I41- which, is .adjustablysecured on the-shaft. .I,33,-.by

a screw I50. The ends ofthese cab1es..l43,and I44 are disposed remotely from eachother andextend towards each other (Figure 1) etc where:

they pass over and down the.opposite sides. of a pair of grooved idler pulleys I5I, andI52 which are rotatablymountedon a ,stud. I53 and this stud, I53 is. fixedly mounted in ahorizontally diSr'. posedportion 15.4 of a substantially inverted L-.'. shaped bracket I 55 whichis secured,. by means of bolts I56,-to the intermediate frame member pairofgr'ooved pulleysIBI and I52 extend downwardly and each, of them are mounted at their lower;.ends in block.1nembers Iand I6I respectively; each of which are identical and one of which is shown in detail in Figure 10. The cables I43 and I44'are secured in the block mem bers I60 and I6I, respectively, by set screws I62 and these block members I 69 and I6I are slidably mounted on restricted portions I64 ofblocki members I65 and are secured on the same by lock nuts I66. The block members I65'are a'djustably secured, byset screws I63, on transverse lever bars I61 and I10 and near one end thereof? The lever bars I61 and I10 extend rearwardly and are disposed'in spaced relation to each other and are pivotally mounted at their other ends on the ends of a transverse shaft I1I (Figure 3),- which is fixedly secured in a bearing block I12 disposed between the'other ends of the levers I61 and 110 and which is fixedly secured, .'by any suitable; means such'as a bolt I13, to a tally disposed channel member I14.

The channel member.l14 is secured, by anysuitable means such as bolts I15, to the same intermediate frame member I2 on which the bracket- I55 .is mounted, and these bolts I 15 penetratebneofithe flangesrof the channel member I14. In this instance, the bolts I15 are the same bolts that normally secure an intermediate bearing block'to the intermediate framemember I2 and in whichan intermediate portion of the rock shaft is normally. oscillatably mounted.

The bars I61 and I10 are pivotally mounted at their rearends on the shaft I1I adjacent each side of the bearing block I12 and disposed against the remote sides of the bars I61 and I10 are collars I and I8I, respectively, which are releasably secured on the shaft I1I to thereby prevent endwise movement of the lever bars I61 and I10 on the shaft I1I.

Secured to intermediate portions of each or" semicircular portion of smaller diameter, indi' cated at I98. These cam wheels I and.. I96 are fixedly mounted on a transverse shaft 200 which is rotatably mounted in bearing blocks 20I which are secured'by any suitable means such as screws 262 to the upper flanges of the two spaced vertically disposed channel bars 203 and 204, which are disposed at each side of the foam wheels I95 and I96 and extend downwardly and their lower flanges are welded to the upper surface-ofthe' horizontally disposed channel bar I14.

The right-hand end or the shaft 200, in Fame Thelcables I Mien c1144 after passing over the 1 horizon- 3i.hasifixedlyrmountedithereona collar- 2| Il whichengages theright -hand1surface of the right -handblock 2111 i which thereby prevents endwisemove merit". of; the shaft-200; The otherend of the shaft-2B0 has-.oscillatablymounted'thereon a bell crank 2| I comprising angular-1y disposediarms :2 2 audit I3iinteg'ral therewith. The arm .21 2 has pivota-llymountedthereon, as at: 2 I 4, aratchet pawl 2-I$ which is adapted to engage sprocket toothed.

segments 2 Ilof asprooketiwheel 2 I8; Theratcliet pawl: 2 I 6 is 1 urged. toward the segments 2-1 1 by a tension spring 2I5 which is connected to the ratchet. pawl atone endand the other end of W-hlCl'lFiSL connected to a collar. or. sleeve-2 I9. loosely.

mounted on the'transverse shaft 200.

- The :sprocket toothedsegments 2 I I are securedto:the=sprocket wheel 2I8 perso, by. any suitable means suchasz'screws 228' and these screws 22%)- penetrated open-endedslots 22! in the sprocket toothed segments; 2Iiv to thusfacilitate the removalzof 1 the same from the-sprocket-wheel 218' pert-sense that these segments 2I'I. may be re- Placed by like segments, or in the instance that it is .desired1to change the timing relation between:

the-take-up of the tapes .75 and the reciprocatory movement of the horizontally disposed rectangular,bars l33', ongwhichtheblades I25 and I28 are mounted; the. overall diameter of the segments 2-.I"I=-may be. decreasedior increased as desired-to obtain this..result,.by usinglonger segments.

Thgzarm 2'! 3. of the bellcrank 25 I, which projects downwardly from the shaft 228, hasan elongatedslot' 225-.therein which is penetrated by a StUdiZZGL,\VhiCh has sliding movement lengthwise of the slot 225 and isrconfined in thearm 2|?- of -thebjell crank 2! I by a locknut 227;

The stud :225'. has a restricted portion 228 integraltherewith which-extends through a link229- (Figure ;-3) and is secured to the same by a nut 224-which is threadablymounted onthe restricted I portion 2 28- of the stud 226'. The link: 229 extends'idownwardlyandis fixedly secured'toa substantiall horizontally disposed bar 2331' (Figure-2)., by a bolt-2M which .penetratesan adjustment slot 232-inthe horizontal bar 233;- horizontal bar extends rearwardly; onto-the right in Figure 2; and isfixedly'securedat its rear end .toan upwardly projecting'portion 23d ofca treadle bar 235, by any. suitable means such asabolt 236which penetrates an;adjustment:slot: Q,

231 in-the. upwardly projecting; portion- 234;

Theupwardly projecting portion 234w is connected to the treadle bar 235 by a-n-inwardly pro+- jecting portion 240-(Figure 3) and this-treadle barhas integral therewith-abearingportion 255 which is-c1amped, by any suitable means such asascrewl-ii (Figure 2') to the rocker shaft 221 and the treadlebar 235-extends-iorwardiy and;

has welded. thereto an-inverted T-shaped'member 245. (Figure 2-) 'Now, as the lay Bflmovestoward its rearmost.

disposed and forwardly projecting bar 25I having,

an enlarged portion, 252 on thefront-end thereof. Theenlarged portion 252; may .be integral with the The Gil

the bar 251'- or,- as shown in this instance; the enlarged portion 252" may be secured" to-the-ban 222i; by any suitablemeans such as a; bolt 2585 This enlarged portion 252 isslidably penetrated by he horizontally disposedrectangularshaft I33 onwvhich theblade assemblies I and "Mi an. secured and is locked in position" on" thexshaft las byaset screw 254.

Every time the lay 30- moves toits rearmost pcsitien, the inverted r shaped-member 2E5? at? the end of the treadle bar 235-; engages the lower' end'of the vertically: disposed shaft 246 to-thus raise the-horizontally disposed shaft I33 slig-ht1y' and to thus cause reciprocatoryvertical motion' tozbatransmitted to the shaft I33 with. everyrearwardstroke of the'lay 30.

It: is manifest that, in the event that the lcom is very broad, and if it is deemed necessary; there maybe any number of the treadlebars' 235- mounted on the rocker shaft 22' andthese treadle bars 235-will, of course, not require-the upwardl proj ecting portion 234' integral therewith. These treadle bars 235wou1dthen have tlo'e associated members 246, 25L and 252 sons to" assistain transmitting reciprocatory vertical motion to. the rectangular shaft I333 The inverted T-shapediportion 245on-tlieend of the treadle bar 235 is of suficient width that the horizontal sliding movement of the*rec-- vtangulawshaft I33 will not cause the'verticallyi disposed rod ls to'move: out of I alignment with the. inverted T-shaped member 2'45as it moves upwardly. it is thus seen that as-the rocker shaft" iiiosciilates, by means of the swords" 24' and 25,v the treadieber 235 imparts movement totheup wardly extending portion 234; thelink 229; and the 233, to thus cause the remote ends of the arms 225and'2'l2 to oscillate; Now; astlie arm 2'i2 moves in a counterclockwise direction; as observed in Figure 2, the ratchet pawl'-2l6'ene gages-the ratchet toothed segmentsZH to'partiaily rotate the shaftfiflil' in step byst'ep relation in counterclockwise direction with' each rota;- tion of the crank shaft 56;

This step by step partial'rotationof ithe'sheit" 28E] imparts like rotation to the cam wheels I95 and EGG-so that, asshowninFigure-3, the'roller. I moves along theperiphery of the camLWheeI. I until it passes off the raisedportion I91 onto. the-smaller semicircular portion I98. and simul taneously the roller I9I' moves from the smaller semicircular portion I98 orthe cam wheel I58 onto the raisedsernicircular portion I91 and thus. the lever. I B'Imoves upwardly simultaneously with. downward movement of the lever. H0, at their. outer ends. This, of course, causes the cable. I44 to pull the shaft I33irom right to left, as observedl' in Figure. l, and permits enough slack in the cable I 43Isothat the cableIM may move thisshaftlfl. from right .to left in Figure 1.

Conversely, when the roller. I 901-moves from-the: smaller semicircular. portion I98.of the cam:.wheel.. I95 to the enlarged portion I91 and the roller,=l9lmoves from the enlarged portion I91 to. the; smaller. portion. libioithe; cam. wheel I95 the rectangular. shaft E33 then: moves fromrleftv to right or back to the position shown in Figure: 1... Itis thus seen .thatthezblades I25 and I26:on the horizontal shaft. I33 move, say from left .to-right. and .then-theypause-for asufficient lengtlrofitime: to .sever*ther-cross-over warp, threads 85, as 50b!- served in Figure l, and-then theblades: I25iandd I26 move fromright-to;left, as observed-1 inrsFi'ggure :1,-. so.:that :the blade I 26rsevers the .crosssovexr threads 85 and this is repeated as long as the loom is in operation.

It has already been described how the blades I25 and I26 are caused to reciprocate upwardly and downwardly in very sudden and short strokes by the oscillation of the rocker shaft 22 'and, of course,'this procedure continues at all times regardless of which blade I25 or I26 is doing the severing operation. ,This assures a smooth and even cutting'ofithe cross-over'thread's andalso,

if the blades I25 and I26 happen to be a little dull, the vibration of the blades I25 and I25 further' increases the efficiency of the cuttingedge of the blades I25 and I26.

It has already been described how the ratchet pawls Ill] and III impart step by step rotation to the ratchet wheel 95 on theshaft 94 to thus transmit step by step partial rotation to the shaft 9| on which the take-up rolls 90 are secured.

Now, it often happens-that the ratchet pawls I I0 H6, as the case may be,'would not sever'the crossover-threads 85 or 86 but would sever the'con-' nec'ting .strapse'lB "or-I9, :as the case maybe, in-

stead, .and it is probable lthat'the operator of the loomjwould notice 'this'at once,'and proper steps could be taken to assure that the ratchet pawls H0 and III would engage'the wheel95, such'as by removing anyacumulations of lint or other foreign matter from theratchet wheel 95 or by replacing the ratchet wheel in the event that a Qfith rte hainxthe;ratchet:wheel-are;broken away.

Heretofore it. has been impossible to insure that all of the cross over straps I8 and I9 would be of identical length by means of a severing operation: performed-by-apparatus attached to the loom W3, in. L'-

while in the drawings and specification -I-have described a particular form of tape which is being out, which is known as a staggered ladder tape with two parallel ladders woven somewhat inside each edge of the tape and with one ladder stitched in at a point one-half the length of the other ladder, it is quite evident that by changing the timing and shape of the cams, many other types of tape could be cut with this apparatus, such as a double ladder tape and tapes having two parallel ladders on one side, and various other types of tapes.

In the drawings and specification there has been set forth a preferred embodiment of the invention, and although specific terms are em ployed, they are used in a generic and descriptive sense only, and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. In combination with a loom having mechanism for weaving a plurality of ladder tapes, said loom having a rock shaft and having means for taking up on the tapes as they are woven, said ap s. 2 2

l l ll) tapes having cross-over threads thereon, means for severing the cross-over threads of said tapes, means for moving the means for severing the cross-over threads into a severing position in advance of movement of the cross-over threads with the tapes, means for connecting the means for moving the means for severing the cross-over threads of said tapes to the rock shaft and whereby the means for moving the means for severing thecros's-over threadsofisaid'tapes are actuated by oscillation of the rock shaft to cause the means for "severing the cross-over threads to acton'the'same inadirection opposite to the direction of travel of the tapes.

11s aloom forweaving pairs of superposed tapes between which cross-straps are interwoven, the'ends of said cross straps being connected to each other by cross-over threads, said loom havinga rock shaft and means for moving the woven superposed tapes as they are woven, cutting apparatus 'for'severing the cross-over threads of said"tapes, means actuated by'said rock shaft' for effecting'movement of the cutting apparatus" crosswise of the travel of the tapes and in advance of movement of -the cross-over threads to thereby sever" thecross-over'threads with the cutting apparatus acting on the same in a direc-* tion, opposite to the direction of travel of the a 3. Ina loom for 'weavingip'airs of superposed tapes between which cross-strapsare interwoven, the ends of-said cross straps being connected to ejaclroither by cross-over threads, said loom hav-' inga rock shaft and means for moving the woven superposed tapes as they are woven, cutting ap-' paratus for severing the cross-over threads of said tapes, means actuated by the rock shaft for moving the cutting apparatus into a cutting position in advance of the cross+over threads for severing the-,cross-ov'erf threads and means actuatedjby the rock" shaft for repeatedly imparting a consistent range of intermittent reciprocatory movement to the cutting apparatus in a vertical direction during each severing operation to furth'er assist in the severingoperation.

"4. In a. loom on which'laddertapes for Venetian'blinds are woven, said tapes comprising a pair of tapes having interconnecting cross straps :and being; connected by, cross.-over threads, an

after they' areiwoven, cutting apparatus forseyering the cross-over thr'adsof sai'dta'psj said cutting apparatus comprising cutting blades, means for effecting movement of said cutting blades in a direction transverse to and in timed relation with the movement of said tapes to bring the cutting apparatus into cutting position with relation to the tapes for the severing op eration, said means for effecting movement of the cutting blades comprising a horizontal bar on which the blades are mounted, a pair of rotatable pulleys mounted below the horizontal bar, a pair of cables connected to the horizontal bar in spaced relation to each other, said cables extending toward each other to where they pass over the rotatable pulleys, a pair of spaced forwardly and rearwardly extending lever bars pivoted at one end, means for connecting the other ends of the cables to'the free ends of the respective lever bars, a transverse shaft rotatably mounted between the horizontal bar and the rearwardly and forwardly extending bars, a pair of cam wheels fixedly mounted on the transverse I 5 shaft, the lever bars being adapted to engage the 11 surface of the cam wheels, a ratchetwheel fixedly mounted on the transverse shaft, 2. bell crank disposedbetween the ratchet wheel and the cam Wheels, a ratchet pawl pivotally connected to one end of the .bell crank and being adapted to engage the ratchet wheel,. means driven by the rock shaft of the loom for transmitting oscillatory motion to the ends of the bell crank to cause thelratchet pawl to engage the ratchetwheel intermittently to thereby transmit intermittent partial rotation to the ratchet wheel to thus cause'intermittent reciprocatory movement of the rectangular bar longitudinally of the horizontal bar.

5. In a structure according to claim 4, a treadle bar secured to the rock shaft and extending from the same forwardly, a vertically disposed shaft, the forward end of said treadle bar being adapted to engage the lower end of said vertically disposed shaft, means connecting the upper end of said vertically disposed shaft to the horizontal bar comprising means for transmitting vertical reciprocatory motion to the horizontal bar through oscillation of the rock shaft.

6. In a loom for weaving a pair of superposed tapes connected together by ladder straps and by cross-over threads interwoven between the two straps, said loom having a rocker shaft, means for severing the crossover threads comprising an oscillatable bar having knives thereon adapted to move into the path of the cross-over threads on one side of the tapes and to be moved to cause its other knife to be moved into the path of the cross-over threads on the other side of the tapes alternately, means driven by the rocker shaft of the loom for intermittently raising the oscillatable bar and the knives associated therewith to quickly sever the cross-over threads.

'7, In a structure according to claim 6, means driven by the rocker shaft of the loom for advancing the tapes as woven through the loom.

8. In a loom for weaving Venetian blind tape which comprises apair of tape members disposed in superposed relation and having ladder straps connecting the two in offset relation at each of the edges of the tape and having cross threads connecting the two tapes together, means for severing the cross threads comprising a laterally oscillatable bar having a pair of knives thereon, means for moving the bar longitudinally with its knives to cause one of the knives to be in the path of the'cross threads near one side of the tapes and then for moving the bar to withdraw the first- 12 named knife out of the path of the cross threads and the interconnecting tapes and, to move the other knife into the path of the cross threads and means for moving the bar with its knives vertically upon each pick of the loom for severing the cross threads.

9. In a loom for weaving Venetian blind tapes which comprise two superposed tapes connected together by cross connecting straps and woven together by cross threads at spaced intervals along each side, said loom having a rocker shaft, means for severing the cross threads comprising a horizontally disposed bar having a pair of cutter means thereon, means driven by the rocker shaft of the loom for moving said bar longitudinally to cause one of the cutter means to be disposed within the path of the cross threads on one side of the tapes and to move the other cutter means out of the path of the cross threads and the connecting tapes on the other side of the tapes, means for imparting vertical oscillations to the horizontally disposed bar to assist the cutter means in cutting the cross threads, and means for moving the horizontally disposed bar in a reverse direction to move the first-named cutter means out of the path of the first-named cross threads on one side of the tapes and into the path of the cross threads on the other side of the tapes to sever the cross threads on the other side of the tapes. 7

10. In a structure according to claim 9, means driven by the rocker shaft of the loom for taking up the tapes as they are woven.

11. In a structure according to claim 9, means driven by the loom and operable upon each pick of the loom for taking up the tapes as woven.

12. In a structure according to claim 9, the means driven by the loom for moving the longitudinally extending bar with its cutter being 0perable after a predetermined number of picks have been executed by the loom.

GEORGE S. MACK.

REFERENCES CITED -The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,872,993 Lundgren Aug. 23, 1932 2,346,551 Brindle Apr. 11, 1944 2,371,164 Gibbons Mar. 13, 1945 

